Nonslip brick



Patented Nov. 11, 1941 NONSLIP BRICK Wallace T. Montague,Worcester, Mass, assignor to Norton Company, Worcester, Mass., a corporation of Massachusetts I Application February 14, 1939, Serial No. 256,331 I 3 Claims.

The invention relates to non-slip bricks and tiles.

One object of the invention is to provide an apparatus for manufacturing non-slip tile and bricks by the use of which they can be manufactured economically. Another object of the invention is to provide a packing house brick which will wear indefinitely and prevent accidents.v Another object of the invention is to provide an extrusion method for the forming of bricks with abrasive in one surface only. Another object of the invention is to form a composite brick structure in a single operation. Another object of the invention is to provide an apparatus and method for manufacturing bricks having a layer of abrasive material in accordance with which the ultimate product is integral and not liable to spelling, chippin or separation. Other objects will be in part obvious or in part pointed out hereinafter.

The invention accordingly consists in the features of construction, combinations of elements, arrangements of parts, and in the several steps and relation and order of each of said steps to one or more of the others thereof, all as will be illustratively described herein, and the scope of the application of which will be indicated in the following claims.

In the accompanying drawing illustrating. one of many possible embodimentsof the mechanical features of this invention,

Figure 1. is a vertical sectional view of apparatus for forming green bricks;

Figure 2 is a plan view of the apparatus; and

Figure 3 is a sectional View taken along the line 33 of Figure 1. I

Figure 4 is a perspective view of a brick according to the invention.

As conducive to a clearer understanding of the present invention, it is noted that in packing houses there is a quick accumulation on the floor of waste matter, blood and the like. This has to be cleaned oil at regular intervals or it decays and putrefies which would not be healthful and would aifect the meat. In order to clear the floors, it has been customary to use hot Water or live steam. This would quickly deteriorate any wooden floor and, therefore, brick floors have been provided. Because of reasons of economy, the brick used has been of a cheap variety, for example made of red clay vitrified at a low temperature. Such bricks have not been entirely satisfactory for the reason that they are quite slippery under packing house conditions. and,

ufactured relatively cheaply so thatalthough.

somewhat more expensive than the ordinary plain brick, this will be in part at least compensated for by the increased life of -myproduct,-

whereas the non-slip nature thereof is a definite advantage.

Referring now to Figure 1, I provide a machine comprising legs I supporting a table I I upon which is mounted a hollow cylinder I2. Above the hollow cylinder I2 and communicating with it;

by means of an orifice I3 is a hopper I4. In the hollow cylinder I2 is a feed screw I5.substantial-- ly completely filling the inside of the cylinder I2 and mounted on a small diameter shaft I6 sothat material fed into the hopper I4 will be moved to the right in the cylinder I2. The shaft I6 is supported at the right-hand-end in a journal I I integral with a grid I8 which stops the rotation of the material; The shaft IG-is supported at the left-hand end in a journal formed integral with a cylinder head 2|. On the left-hand end of the shaft: I6 is a bevel gear 22 meshing with a bevel gear 23 on a vertical shaft 24. The shaft 24 is supported in a verticalv thrust bearing 25 5 formed in a bracket 26 fastenedto apair of legs I0. Near the bottom of the, shaft 24 is a bevel gear 2'! meshing with a bevel gear 28 on the lefthand end of a drive shaft 29. A pulley 30 on the drive shaft 29 is connected by a belt 3| to a pulley 32 on the armature shaft 33 of an electric motor 34. Thus the screw I5 is rotated and in sucha direction that material fed into the hopper' I4 will be moved to the right in the cylinder I2.

Integrally formed with the cylinder I2 is another cylinder' 35 whose axis intersects that of the cylinder I2 but is inclined thereto at an angle of about although the'angular relationship is not critical. 'In this cylinder 35 is a feed screw 36 mounted on a shaft 31 which is journalled in a journal 38 formed integral with a grid 39 to stop rotation of the material. The shaft 31 is journalled at its upper end in a journal portion formed in a hopper 4| having a bottom opening 42 communicating with the upper part of the cylinder 35. On the upper end of the shaft 3'! is a bevel gear 43 meshing with a crown gear 44 on the end of a shaft 45 journalled in a journal 46 attached to brackets 41 extending from the hopper 4| to a bracket 48 (see Figure 2) supported by brackets 49 fastened to the table II. On the under side of the bracket 48 is a journal 56 also supporting the shaft 45, on the left-hand endof which is a bevel gear meshing with a bevel gear 52 on the upper end of the shaft 24.

Still referring to Figure 1, a baffle plate 53,

which may be curved and of the same radius as the cylinder 2, intercepts the opening at the I bottom of the cylinder 35 and forms a-continuhoppers I4 and 4| where the materials merge.

An extrusion nozzle 55 closes the cylindrical end of the cylindrical extension |2a and is bolted to itas shown. In cross section the shape of the noz zle 55 gradually changes from 'aci'rcle to a rectangle and the deliveryopening is 'trapezoidal mixtures orsmtaue brick" the table II. I prefer to provide some mechanical means for cutting off the extruded clay, such as a fiyingshear or the apparatus which will now be'described.

Referring now to Figure 1, on the under side of the table II and depending therefrom are a pair stantly fed by the operator-into the hopper I4.

A mixture of this clay and abrasive-grains is constantly fed by the operator into the hopper 4|. Preferably the mixturein the hopper 4| consists of the order of 25% abrasive by volume and 75% clay by volume. The abrasive may be of any suitable variety, but I prefer to use electric furnace fused alumina in grit sizes from 20 mesh to 8 mesh and even coarser. A preferred grit size is 8 mesh grit size. These sizes define abrasive grains which will just pass througha screen having that many meshes to the linear inch inpick' and sley. Other abrasives, however, can readily be used, especially such as silicon carbide and flint (quartz), and the invention is not limited to any particular mesh size of the abrasive used.

"It will -now be seen that the extrusion apparatus forces the ordinary clay mixture through] the cylinder I2 and forces the mixture'of clay and abrasive down the cylinder 35'where thetwo streams merge, the grids I8 and 39 stopping the rotation of the mixture and causing the abrasive mixture to assume a position on-top of'the'plain mixture. Thus through the trapezoidal opening 56 is forced aquantity of ordinary clay Ion the bottom and amixture of clay and abrasive on the top; It is not represented that the line of division is at all times perfectly straightand even butthis is not a matter of great consequence.

The gear ratios of the driving mechanism cause the screw l5 tobe driven about four times as fast as the s'crew'36wliich will feed four times as much ordinary clay as mixture of clay and' abrasive and permit the application of a layer of clayand abrasive on the top of the extrusion mass tofbe approximately one quarter the depth thereof. Theopening- 56 has been referred to-astrapezoidal and it will be noted that it is but slightly removed from a rectangle. In fact, thedateral edgesv can be at right angles to the bottom line near the bottom line and then form an obtuse angle with the top line, The reason for slightly altering theotherwise rectangular shape of -.the orifice- 56 is that during firing, the mixture of clay and abrasive expands more than; the portion'consisting simply of clay so that to produce of journals 66 and 6| for the shaft 29. At the right-hand end of the shaft 29 near the journal 6| is a crowned gear 62 which meshes with a gear 63. Referring now to Figures 1 and 2, the gear 63 is on a shaft 64 to which is fastened a pulley 65 connected by a belt 66 to a'pulley 61 on the end of a transverse shaft-68 which extends over the table II. The shaft 68 may be journailed in suitable journal brackets 69 and 16. Fastened to the shaft 68 are a pair of spiders H; the arms 12 of which have extending between them'wires l3. As the machine is operated, the spiders rotate, carrying the wires downward, which cut off the extruded clay nearly in a plane perpendicular to thepropagation'thereof. Each brick can be quickly trimmed off with a trowel by the man who places them in a kiln to make the end surfaces normalto the top and bottom surfaces.

- The green bricks are now taken to asuitable. ceramic kiln and vitrified at temperatures commonly employed for firing packing house bricks.

Such temperatures are fairly low in the ceramic arts but I will not further describe vitrification of the bricks since that may be done in accordance With usual practice. that the bricks started out trapezoidal in cross section, the expansion brings them approximatelyto rectangular parallelepipeds.

It has been mentioned that the abrasive is of the order of 25%. To obtain a substantial effect from the abrasive, it should constitute at least 10% of the volume of the surface portion. That is to say, the surface area which contains-the abrasive should have on the'surface at least 10% of abrasive material measured by volume. In making this measurement'by'volume, the vertical dimension should betaken as; oneabrasive grain more than 40% abrasive in any part of the block I because more than this amount may cause such differences in the vitrifying that the brickwill be deformed or the abrasive portion may separate from the plain portion.

It-will thus be seen that there has been provided by this invention apparatus, a method and an article in which the various objects hereinabove set forthtogether with many thoroughly practical advantages are successfully achieved. As various possible embodiments might be made of the mechanical features of the aboveinven tion and as the art herein described might be varied in various parts, all without departing from the scope of the invention, it is to be understood that all matter hereinbefore set forth or shown in the accompanying drawing is to be interpreted as illustrative and not in a limiting sense. I

By reason of the fact.

I claim:

1. A non-slip brick comprising a substantially rectangular portion of plain vitrified red brick clay and a substantially rectangular layer integral with said first portion and comprising vitrified red brick clay with not more than 40% and. not less than 10% of discrete particles of abrasive included therein.

2. A brick made of vitrified red brick clay and having its surface modified by an inclusion of between 10 and 40% of fused alumina abrasive grains in the surface area measured by volume.

3. A brick consisting of vitrified red brick clay having a surface containing discrete particles of abrasive which brick, measured to a depth consisting of the vertical dimension of the average abrasive in the surf-ace, has a volume percentage of between l0 and 40% abrasive, the remainder ordinary vitrified red brick clay, the majority of the brick being substantially free from abrasive and consisting of ordinary vitrified red brick 10 clay, the brick being an integral whole.

WALLACE T. MONTAGUE. 

